Coverage analysis is method adopted by many software developers for ensuring consistent, high-quality verification results. Code coverage analysis tools may be installed to provide the coverage analysis for a particular program. Coverage analysis tools may vary in scope and method for obtaining coverage information.
Essentially, coverage analysis is based on the measurement of a design's test suite against a set of objective metrics. Designers will choose metrics based on the stage of their design, the cost of making the coverage measurement and a design group's experience with the usefulness of a particular metric. Code coverage metrics are often the first to be employed because they can be implemented at relatively low cost with automated tools and provide straightforward results.
One method of code coverage instrumentation involves placing “probes” at each block or arc within the logical flow of a program's code. The “probes” refer to a set of instructions that records data about the code. For example, a probe may report out the usage data of a particular portion of the program for analysis. Placing probes in the program provides a powerful method for instrumenting a program.
Performance is a concern in any cases where a user needs to augment code to collect additional data. The overhead imposed by the instrumentation/probes may outweigh the benefits of the code coverage analysis. The performance cost of the probe-based analysis may be significant due to the level of coverage data provided. What is needed is method for instrumenting a program that provides a comparable level of data as provided by probe-based analysis while improving performance costs.